TWI635433B - Circuit and method for touch sensing - Google Patents

Circuit and method for touch sensing Download PDF

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TWI635433B
TWI635433B TW106140603A TW106140603A TWI635433B TW I635433 B TWI635433 B TW I635433B TW 106140603 A TW106140603 A TW 106140603A TW 106140603 A TW106140603 A TW 106140603A TW I635433 B TWI635433 B TW I635433B
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capacitance detection
self
detection circuit
voltage
capacitor
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TW106140603A
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Chinese (zh)
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TW201926014A (en
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任慶霖
楊思哲
朱家頤
江忠霖
張耀叡
陳耿男
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矽統科技股份有限公司
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Priority to US16/198,145 priority patent/US11054933B2/en
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    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F3/00—Input arrangements for transferring data to be processed into a form capable of being handled by the computer; Output arrangements for transferring data from processing unit to output unit, e.g. interface arrangements
    • G06F3/01—Input arrangements or combined input and output arrangements for interaction between user and computer
    • G06F3/03—Arrangements for converting the position or the displacement of a member into a coded form
    • G06F3/041—Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
    • G06F3/0416—Control or interface arrangements specially adapted for digitisers
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F3/00—Input arrangements for transferring data to be processed into a form capable of being handled by the computer; Output arrangements for transferring data from processing unit to output unit, e.g. interface arrangements
    • G06F3/01—Input arrangements or combined input and output arrangements for interaction between user and computer
    • G06F3/03—Arrangements for converting the position or the displacement of a member into a coded form
    • G06F3/041—Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
    • G06F3/0416—Control or interface arrangements specially adapted for digitisers
    • G06F3/04166—Details of scanning methods, e.g. sampling time, grouping of sub areas or time sharing with display driving
    • G06F3/041662—Details of scanning methods, e.g. sampling time, grouping of sub areas or time sharing with display driving using alternate mutual and self-capacitive scanning
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F3/00—Input arrangements for transferring data to be processed into a form capable of being handled by the computer; Output arrangements for transferring data from processing unit to output unit, e.g. interface arrangements
    • G06F3/01—Input arrangements or combined input and output arrangements for interaction between user and computer
    • G06F3/03—Arrangements for converting the position or the displacement of a member into a coded form
    • G06F3/041—Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
    • G06F3/044—Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means by capacitive means
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F2203/00—Indexing scheme relating to G06F3/00 - G06F3/048
    • G06F2203/041—Indexing scheme relating to G06F3/041 - G06F3/045
    • G06F2203/04104—Multi-touch detection in digitiser, i.e. details about the simultaneous detection of a plurality of touching locations, e.g. multiple fingers or pen and finger

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Theoretical Computer Science (AREA)
  • Human Computer Interaction (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Position Input By Displaying (AREA)

Abstract

一種觸控偵測電路，其包含一驅動單元、一自容偵測電路、一互容偵測電路以及一控制電路。該驅動單元用來產生一驅動訊號。該自容偵測電路用來產生一自容偵測結果。當該自容偵測電路以及該互容偵測電路之間的電壓達到一參考電壓時，該互容偵測電路接收該驅動訊號進行互容偵測，產生一互容偵測結果。該控制電路接收並計算該自容偵測結果以及該互容偵測結果，以產生一偵測結果。通過本發明的觸控偵測電路可以提高準確率及感測效率。 A touch detection circuit includes a driving unit, a self-capacitance detection circuit, a mutual capacitance detection circuit and a control circuit. The driving unit is used for generating a driving signal. The self-capacitance detection circuit is used to generate a self-capacitance detection result. When the voltage between the self-capacitance detection circuit and the mutual-capacitance detection circuit reaches a reference voltage, the mutual-capacitance detection circuit receives the driving signal for mutual-capacitance detection, and generates a mutual-capacitance detection result. The control circuit receives and calculates the self-capacitance detection result and the mutual-capacitance detection result to generate a detection result. The touch detection circuit of the present invention can improve accuracy and sensing efficiency.

Description

觸控偵測電路及方法 Touch detection circuit and method

本發明係關於一種觸控偵測方法，尤指一種可同時進行互容及自容偵測的觸控偵測方法。 The invention relates to a touch detection method, and more particularly to a touch detection method capable of performing mutual capacitance and self-capacitance detection simultaneously.

在市面上的消費性電子產品中，多點觸控已成為不可或缺的功能。現今觸控偵測方法，主要分為自容式觸控偵測以及互容式觸控偵，其中互容式觸控偵測相較於自容式觸控偵測更適用於多點觸控，因此也因此互容式觸控廣泛地應用在觸控螢幕中。 Multi-touch has become an indispensable feature in consumer electronics products on the market. Today's touch detection methods are mainly divided into self-capacitive touch detection and mutual-capacitive touch detection. Among them, mutual-capacitive touch detection is more suitable for multi-touch than self-capacitive touch detection. Therefore, mutual capacitive touch is widely used in touch screens.

然而互容式觸控容易受到環境的干擾而影響偵測的結果，如使用者操作時手指是溼的、空氣中的溼度氣/溫度、螢幕上的水珠或汙漬等因素，都會造成偵測的結果錯誤或偏差。 However, mutual capacitive touch is susceptible to environmental interference and affects the detection results, such as wet fingers, humidity / temperature in the air, water droplets or stains on the screen, etc. The result is wrong or biased.

自容式觸控則是較不容易受到環境的干擾。然而自容式觸控偵測無法應用於多點觸控，因此為了達到多點觸控的功能，同時排除環境干擾以提昇觸控偵測的準確度，許多觸控螢幕會同時使用互容式觸控偵測及自容式觸控偵測，電子裝置分別進行互容式觸控偵測及自容式觸控偵測後，計算兩者的數值再判斷偵測的結果。然而如此一來，觸控偵測的時間勢必增加，進而影響電子產品的運行速度。 Self-capacitive touch is less susceptible to environmental interference. However, self-capacitive touch detection cannot be applied to multi-touch. Therefore, in order to achieve the multi-touch function and eliminate environmental interference to improve the accuracy of touch detection, many touch screens will use mutual-capacitive touch at the same time. Touch detection and self-capacitive touch detection. After the electronic device performs mutual-capacitive touch detection and self-capacitive touch detection, respectively, calculate the values of the two and then determine the detection result. However, in this case, the time required for touch detection is bound to increase, which will affect the operating speed of electronic products.

故，有必要提供一種觸控偵測方法，可以同時進行互容式觸控偵測以及自容式觸控偵測，以達到增加多點觸控偵測準確度之目的，同減少偵測所需的時間，以提昇偵測的速度。 Therefore, it is necessary to provide a touch detection method that can perform mutual capacitive touch detection and self-capacitive touch detection at the same time to achieve the purpose of increasing the accuracy of multi-touch detection, and reducing the detection Time required to increase the speed of detection.

本發明提供一種觸控偵測電路，其包含一驅動單元、一自容 偵測電路、一互容偵測電路以及一控制電路。該驅動單元用來產生一驅動訊號。該自容偵測電路用來產生一自容偵測結果。當該自容偵測電路以及該互容偵測電路之間的電壓達到一參考電壓時，該互容偵測電路接收該驅動訊號進行互容偵測，產生一互容偵測結果。該控制電路接收並計算該自容偵測結果以及該互容偵測結果，以產生一偵測結果。 The invention provides a touch detection circuit, which includes a driving unit and a self-capacitor. A detection circuit, a mutual capacitance detection circuit and a control circuit. The driving unit is used for generating a driving signal. The self-capacitance detection circuit is used to generate a self-capacitance detection result. When the voltage between the self-capacitance detection circuit and the mutual-capacitance detection circuit reaches a reference voltage, the mutual-capacitance detection circuit receives the driving signal for mutual-capacitance detection, and generates a mutual-capacitance detection result. The control circuit receives and calculates the self-capacitance detection result and the mutual-capacitance detection result to generate a detection result.

本發明另提供一種觸控偵測方法，其包含對一互容偵測電路以及一自容偵測電路之間的節點充電，在充電過程進行自容偵測；該自容偵測電路偵測一第一電容，以得到該第一電容在一預設時段內的一電壓變化；在該節點的電壓達到一參考電壓時，該互容偵測電路偵測一第二電容，以得到該第二電容之一電壓輸出訊號；一控制電路根據該電壓輸出訊號計算，以得到一偵測結果。 The invention further provides a touch detection method, which comprises charging a node between a mutual capacitance detection circuit and a self-capacitance detection circuit, and performing self-capacitance detection during the charging process; the self-capacitance detection circuit detects A first capacitor to obtain a voltage change of the first capacitor within a preset period; when the voltage of the node reaches a reference voltage, the mutual capacitance detection circuit detects a second capacitor to obtain the first capacitor One of the two capacitors outputs a voltage signal; a control circuit calculates based on the voltage output signal to obtain a detection result.

本發明尚提供一種觸控偵測方法，其包含對一互容偵測電路以及一自容偵測電路之間的節點充電，在充電過程進行自容偵測；該自容偵測電路偵測一第一電容，以得到該第一電容達到一參考電壓所需的一時間值；在該節點的電壓達到一參考電壓時，該互容偵測電路偵測一第二電容，以得到該第二電容之一電壓輸出訊號；一控制電路根據該電壓輸出訊號計算，以得到一偵測結果。 The invention also provides a touch detection method, which comprises charging a node between a mutual capacitance detection circuit and a self-capacitance detection circuit, and performing self-capacitance detection during the charging process; the self-capacitance detection circuit detects A first capacitor to obtain a time value required for the first capacitor to reach a reference voltage; when the voltage of the node reaches a reference voltage, the mutual capacitance detection circuit detects a second capacitor to obtain the first capacitor One of the two capacitors outputs a voltage signal; a control circuit calculates based on the voltage output signal to obtain a detection result.

本發明利用互容式觸控偵測及自容式觸控偵測，以提高觸控偵測結果的正確率。並且在互容偵測電路與自容偵測電路之間的電壓達到一參考電壓的過程進行自容式觸控偵測，在互容偵測電路與自容偵測電路之間的電壓達到一參考電壓後進行互容式觸控偵測，藉此有效的同時進行互容式及自容式觸控偵測，提高感測的效率。 The invention uses mutual-capacitive touch detection and self-capacitive touch detection to improve the accuracy of touch detection results. And the self-capacitive touch detection is performed when the voltage between the mutual capacitance detection circuit and the self-capacitance detection circuit reaches a reference voltage, and the voltage between the mutual capacitance detection circuit and the self-capacitance detection circuit reaches one. Mutual-capacitive touch detection is performed after the reference voltage, thereby effectively performing mutual-capacitive and self-capacitive touch detection to improve sensing efficiency.

1‧‧‧觸控偵測電路 1‧‧‧touch detection circuit

10‧‧‧驅動單元 10‧‧‧Drive unit

20‧‧‧互容偵測電路 20‧‧‧ Mutual capacitance detection circuit

40‧‧‧自容偵測電路 40‧‧‧Self-capacity detection circuit

60‧‧‧充電單元 60‧‧‧Charging unit

80‧‧‧控制電路 80‧‧‧Control circuit

82‧‧‧轉換單元 82‧‧‧ conversion unit

第1圖：本發明觸控偵測電路第一實施例之電路示意圖。 FIG. 1 is a circuit diagram of a first embodiment of a touch detection circuit according to the present invention.

第2圖：本發明觸控偵測電路第一實施例之第一種時序圖。 FIG. 2 is a first timing diagram of the first embodiment of the touch detection circuit of the present invention.

第3圖：本發明觸控偵測電路第一實施例之第二種時序圖。 FIG. 3 is a second timing diagram of the first embodiment of the touch detection circuit according to the present invention.

第4圖：本發明第二實施例之電路示意圖。 FIG. 4 is a schematic circuit diagram of the second embodiment of the present invention.

第5圖：本發明第三實施例之電路示意圖。 FIG. 5 is a schematic circuit diagram of a third embodiment of the present invention.

第6圖：本發明第四實施例之電路示意圖。 FIG. 6 is a schematic circuit diagram of a fourth embodiment of the present invention.

為了讓本發明之上述及其他目的、特徵、優點能更明顯易懂，下文將特舉本發明較佳實施例，並配合所附圖式，作詳細說明如下。再者，本發明所提到的方向用語，例如上、下、頂、底、前、後、左、右、內、外、側面、周圍、中央、水平、橫向、垂直、縱向、軸向、徑向、最上層或最下層等，僅是參考附加圖式的方向。因此，使用的方向用語是用以說明及理解本發明，而非用以限制本發明。 In order to make the above and other objects, features, and advantages of the present invention more comprehensible, the following describes the preferred embodiments of the present invention and the accompanying drawings in detail, as follows. Furthermore, the directional terms mentioned in the present invention include, for example, top, bottom, top, bottom, front, back, left, right, inside, outside, side, periphery, center, horizontal, horizontal, vertical, vertical, axial, The radial direction, the uppermost layer, or the lowermost layer, etc., are only directions referring to the attached drawings. Therefore, the directional terms used are for explaining and understanding the present invention, but not for limiting the present invention.

請參照第1圖，第1圖為本發明之觸控偵測電路之電路示意圖。觸控偵測電路1包含一驅動單元10、一互容偵測電路20、一自容偵測電路40以及一控制電路80。驅動單元10產生偵測訊號，互容偵測電路20進行互容式觸控偵測，自容偵測電路40進行自容式觸控偵測，控制電路80針對互容式偵測電路20以及自容式偵測電路40所輸出的結果進行計算，並產生觸控發生的位置座標。 Please refer to FIG. 1. FIG. 1 is a schematic circuit diagram of the touch detection circuit of the present invention. The touch detection circuit 1 includes a driving unit 10, a mutual capacitance detection circuit 20, a self-capacitance detection circuit 40, and a control circuit 80. The driving unit 10 generates a detection signal, the mutual capacitance detection circuit 20 performs mutual capacitance touch detection, the self capacitance detection circuit 40 performs self capacitance touch detection, and the control circuit 80 targets the mutual capacitance detection circuit 20 and The result output by the self-capacitive detection circuit 40 is calculated, and a position coordinate at which the touch occurs is generated.

驅動單元10產生一驅動訊號，依據電路特性及需求，該驅動訊號可以是方波、三角波、鋸齒、弦波等訊號源。驅動單元10產生驅動訊號並傳送至互容偵測電路20，自容偵測電路40包含一電壓源或電流源，該電壓源或電流源對互容偵測電路20與自容偵測電路40之間的節點n充電。在節點n的電壓達到達到一參考電壓Vref的過程中，自容偵測電路40可先進行自容式觸控偵測。而當節點n電壓充電到參考電壓Vref後，互容偵測電路20進行互容式觸控偵測。即在互容偵測電路20的電壓充電到Vref的過程中，自容偵測電路40便可利用電壓充電時的階段來進行自容式觸控偵測，使得互容式觸控偵測以及自容式觸控偵測可以同時進行，以縮短偵測所需的時間，增加觸控感測的速度。 The driving unit 10 generates a driving signal. The driving signal may be a square wave, a triangle wave, a sawtooth, a sine wave, or other signal sources according to circuit characteristics and requirements. The driving unit 10 generates a driving signal and transmits it to the mutual capacitance detection circuit 20. The self-capacitance detection circuit 40 includes a voltage source or a current source. The voltage source or current source pairs the mutual capacitance detection circuit 20 and the self-capacitance detection circuit 40. Charge between nodes n. When the voltage of the node n reaches a reference voltage Vref, the self-capacitance detection circuit 40 may perform self-capacitive touch detection first. After the voltage at the node n is charged to the reference voltage Vref, the mutual capacitance detection circuit 20 performs mutual capacitance touch detection. That is, during the process of charging the voltage of the mutual-capacitance detection circuit 20 to Vref, the self-capacitance detection circuit 40 can use the stage of voltage charging to perform self-capacitive touch detection, so that the mutual-capacitance touch detection and Self-capacitive touch detection can be performed simultaneously to reduce the time required for detection and increase the speed of touch sensing.

請一併參照第2圖，第2圖所示為本發明觸控電路第一實施例的第一種時序圖。在第一實施例第一種時序圖中，當電壓充電到Vref時，便可進行互容式觸控偵測，而在充電的過程中，則可利用電壓爬升的變化 來進行自容式電容偵測。詳細的觸控偵測步驟如下：對互容偵測電路20以及自容偵測電路40之間的節點n充電。在自容式觸控偵測中，自容偵測電路40偵測一第一電容Cs的電壓值，並計算第一電容Cs在自容偵測階段ts內的電壓變化量，以第2圖所示為例，在自容偵測階段ts期間，第一電容Cs的起始電壓以及最終電壓分別是0以及Vs，因此電壓變化即為Vs。當Vs值越小，代表第一電容Cs的電容值越大，在自容式觸控偵測中，當觸控發生時第一電容的電容值會變大，因此再通過控制電路80比較第一電容Cs與參考電容的電容值(即比較第一電容Cs與觸控未發生時的電容值)，即可得知在第一電容Cs上是否有觸控發生。 Please refer to FIG. 2 together, which is a first timing diagram of the first embodiment of the touch circuit of the present invention. In the first timing diagram of the first embodiment, when the voltage is charged to Vref, mutual capacitive touch detection can be performed, and during the charging process, the change in voltage climb can be used For self-capacitance detection. The detailed touch detection steps are as follows: the node n between the mutual capacitance detection circuit 20 and the self-capacitance detection circuit 40 is charged. In the self-capacitive touch detection, the self-capacitance detection circuit 40 detects a voltage value of a first capacitor Cs, and calculates a voltage change amount of the first capacitor Cs in the self-capacitance detection stage ts. As shown in the example, during the self-capacitance detection phase ts, the starting voltage and the final voltage of the first capacitor Cs are 0 and Vs, respectively, so the voltage change is Vs. When the value of Vs is smaller, it means that the capacitance of the first capacitor Cs is larger. In the self-capacitive touch detection, the capacitance of the first capacitor becomes larger when a touch occurs. A capacitance value of a capacitor Cs and a reference capacitor (that is, comparing the capacitance value of the first capacitor Cs and a capacitance value when no touch occurs) can be used to know whether a touch occurs on the first capacitor Cs.

在自容偵測階段ts後，節點n的電壓充電到可以進行互容式觸控偵測的參考電壓Vref，此時互容偵測電路20便可於互容偵測階段tm進行互容式偵測。互容偵測電路20偵測一第二電容Cm，依據驅動單元10發出的驅動訊號，互容偵測電路20會產生輸出電壓Vm，通過控制電路80可以計算輸出電壓值。在互容式觸控偵測中，當觸控發生時，第二電容Cm的電容值會變小，相對的Vm值會變小，因此通過控制電路80計算Vm值的變化(即與觸控未發生時的Vm值比較)，即可得知觸控是否發生。控制電路80接收Vs以及Vm，根據自容偵測結果Vs以及互容偵測結果Vm計算出面板上觸控發生的位置座標，及觸控程度大小。 After the self-capacitance detection phase ts, the voltage of the node n is charged to the reference voltage Vref for mutual-capacitive touch detection. At this time, the mutual-capacitance detection circuit 20 can perform the mutual-capacitance detection during the mutual capacitance detection phase tm Detect. The mutual capacitance detection circuit 20 detects a second capacitor Cm. According to the driving signal sent from the driving unit 10, the mutual capacitance detection circuit 20 generates an output voltage Vm, and the output voltage value can be calculated by the control circuit 80. In mutual-capacitive touch detection, when a touch occurs, the capacitance of the second capacitor Cm becomes smaller and the relative Vm value becomes smaller. Therefore, the change in the Vm value is calculated by the control circuit 80 (that is, the same as the touch Vm value comparison when not happening), you can know whether touch occurs. The control circuit 80 receives Vs and Vm, and calculates the position coordinates and the degree of touch of the touch on the panel according to the self-capacitance detection result Vs and the mutual capacitance detection result Vm.

第3圖為本發明第一實施例的第二種時序圖，第一實施例的第二種時序圖與第一種時序圖不同的是，在第二種時序圖的自容式觸控偵測中，自容偵測電路40中是偵測第一電容Cs達到參考電壓所需的時間，再與參考電容充電到參考電壓的所需的時間作比較，以計算自容偵測電路40上是否有觸控發生，而當電壓達到互容式觸控偵測的工作電壓後，互容偵測電路20便可進行觸控偵測。 FIG. 3 is a second timing diagram of the first embodiment of the present invention. The second timing diagram of the first embodiment is different from the first timing diagram in that the self-capacitive touch detection in the second timing diagram is different. In the test, the self-capacitance detection circuit 40 detects the time required for the first capacitor Cs to reach the reference voltage, and then compares the time required for the reference capacitor to charge to the reference voltage to calculate the self-capacitance detection circuit 40. Whether a touch occurs, and when the voltage reaches the working voltage of the mutual capacitance touch detection, the mutual capacitance detection circuit 20 can perform touch detection.

本發明第一實施例的第二種時序圖的詳細步驟如下：對互容偵測電路20以及自容偵測電路之間的節點n充電。在自容式觸控偵測中，自容偵測電路40偵測第一電容Cs充電到Vref所需的時間t21，而參考電容(即觸控未發生時的第一電容Cs)充電到Vref所需的時間為t11。當電容充電所需的時間越短，即代表其電容值越小，而在自容式觸控偵測中，當觸控 發生時，第一電容Cs的電容值會變大，因此經由比較t11以及t21的數值，就可以計算出第一電容Cs的電容值是否變大，以此判斷觸控是否發生。當節點n電壓充電到互容式觸控偵測所需的工作電壓後，互容偵測電路20便可依據驅動單元10發出的驅動訊號產生輸出電壓Vm。在互容式觸控偵測的t3階段中，當觸控發生時，第二電容Cm的電容值會變小相對的Vm值會變小，因此通過控制電路80計算Vm值的變化(即與觸控未發生時的Vm值比較)，即可得知觸控是否發生。控制電路80接收t21以及Vm的數值後，根據自容偵測結果t21以及互容偵測結果Vm計算出面板上觸控發生的位置座標，及觸控程度大小。 The detailed steps of the second timing diagram of the first embodiment of the present invention are as follows: charge the node n between the mutual capacitance detection circuit 20 and the self-capacitance detection circuit. In the self-capacitive touch detection, the self-capacitance detection circuit 40 detects the time t21 required for the first capacitor Cs to be charged to Vref, and the reference capacitor (that is, the first capacitor Cs when no touch occurs) is charged to Vref The time required is t11. When the time required for the capacitor to charge is shorter, it means that its capacitance value is smaller. In self-capacitive touch detection, when the touch When this occurs, the capacitance value of the first capacitor Cs will increase. Therefore, by comparing the values of t11 and t21, it can be calculated whether the capacitance value of the first capacitor Cs has become larger, thereby determining whether a touch occurs. After the voltage of the node n is charged to the working voltage required for the mutual-capacitive touch detection, the mutual-capacitance detection circuit 20 can generate the output voltage Vm according to the driving signal sent from the driving unit 10. During the t3 phase of mutual-capacitive touch detection, when a touch occurs, the capacitance value of the second capacitor Cm becomes smaller and the relative Vm value becomes smaller. Therefore, the change in the Vm value is calculated by the control circuit 80 (that is, Vm value comparison when touch does not occur), you can know whether touch occurs. After receiving the values of t21 and Vm, the control circuit 80 calculates the position coordinates and the degree of touch of the touch on the panel according to the self-capacitance detection result t21 and the mutual capacitance detection result Vm.

根據本發明第一實施例的觸控偵測方法，可以得到準確度較高、且不易受到環境干擾的自容式觸控偵測結果。然而自容式觸控偵測只能做到觸控發生的行或列，舉例來說，多點觸控發生在面板上的(X1,Y1)以及(X2,Y2)時，自容式偵測只能偵測出X1與X2行上、以及Y1與Y2列上有觸控發生，然而無法判斷是(X1,Y1)、(X1,Y2)、(X2,Y1)或(X2,Y2)的哪些點發生觸控。此時利用本發明的觸控偵測電路，在進行自容式觸控偵測的同時，也可以進行互容式觸控偵測，如此一來，在得到自容偵測結果同時，也可以依觸互容偵測結果來得到多點觸控發生的位置，藉此提高多點觸控偵測的準確性。 According to the touch detection method of the first embodiment of the present invention, a self-capacitive touch detection result with higher accuracy and less susceptible to environmental interference can be obtained. However, self-capacitive touch detection can only achieve the row or column where the touch occurs. For example, when multi-touch occurs on the panel (X1, Y1) and (X2, Y2), self-capacitive detection The test can only detect touches on X1 and X2 rows and Y1 and Y2 columns, but it cannot be determined whether it is (X1, Y1), (X1, Y2), (X2, Y1), or (X2, Y2) Which points of the touch occurred. At this time, using the touch detection circuit of the present invention, while performing self-capacitive touch detection, mutual-capacitive touch detection can also be performed. In this way, while obtaining the self-capacitive detection result, it is also possible to The position of the multi-touch occurrence is obtained according to the touch mutual capacitance detection result, thereby improving the accuracy of the multi-touch detection.

本發明尚有一第二實施例，如第4圖所示。觸控偵測電路1包含一驅動單元10、一互容偵測電路20、一自容偵測電路40、一控制電路80以及一充電單元60。充電單元60可以對節點n充電，使其電壓達到互容偵測電路的工作電壓。第二實施例在充電的過程中，自容式偵測電路40可以進行自容式觸控偵測。自容式偵測的方法如第一實施例的第一種時序圖所示，偵測第一電容Cs在充電期間ts中的電壓變化Vs，通過控制電路80比較電壓變化Vs以及參考電壓Vref的大小，在相同的充電時間ts中，所充到的電壓越低，即代表其電容值越大，而在自容式觸控偵測中，當觸控發生時，第一電容Cs的電容值會變大，因此當Vs小於一預設值Vp，或是當Vs與Vref的差異大於一預設值Vd時，即可判斷在第一電容Cs上有觸控發生。或是第二實施例的自容式偵測方式也可以如第一實施例的第二 種時序圖所示，自容偵測電路40偵測第一電容Cs達到參考電壓所需的時間t21，再通過控制電路80比較t21以及參考電容充電到參考電壓Vref時所需的時間t11。充電到參考電壓Vref的時間越久，即代表該電容的電容值越大，而在自容式觸控偵測中，觸控發生時第一電容Cs的電容值會變大，因此當t21大於一預設值tp，或t21與t11的差異大於一預設值td時，便可得知在第一電容Cs1上有觸控發生。 The present invention also has a second embodiment, as shown in FIG. The touch detection circuit 1 includes a driving unit 10, a mutual capacitance detection circuit 20, a self-capacitance detection circuit 40, a control circuit 80, and a charging unit 60. The charging unit 60 can charge the node n so that its voltage reaches the working voltage of the mutual capacitance detection circuit. In the second embodiment, during the charging process, the self-capacitive detection circuit 40 can perform self-capacitive touch detection. The self-capacitive detection method is as shown in the first timing diagram of the first embodiment. The voltage change Vs of the first capacitor Cs during the charging period ts is detected, and the voltage change Vs and the reference voltage Vref are compared by the control circuit 80. Size, the lower the voltage charged in the same charging time ts, the larger the capacitance value, and in the self-capacitive touch detection, when the touch occurs, the capacitance value of the first capacitor Cs It will become larger, so when Vs is less than a preset value Vp, or when the difference between Vs and Vref is greater than a preset value Vd, it can be determined that a touch occurs on the first capacitor Cs. Or the self-capacitive detection method of the second embodiment may also be the same as that of the second embodiment of the first embodiment. As shown in the timing diagram, the self-capacitance detection circuit 40 detects the time t21 required for the first capacitor Cs to reach the reference voltage, and then compares t21 and the time t11 required when the reference capacitor is charged to the reference voltage Vref through the control circuit 80. The longer the time to charge to the reference voltage Vref, the larger the capacitance value of the capacitor. In the self-capacitive touch detection, the capacitance value of the first capacitor Cs becomes larger when a touch occurs, so when t21 is greater than one When the preset value tp, or the difference between t21 and t11 is greater than a preset value td, it can be known that a touch occurs on the first capacitor Cs1.

在充電單元60對節點n充電到工作電壓後，互容式偵測電路20便可進行互容式觸控偵測，根據驅動單元10所產生的驅動訊號產生輸出電壓Vm。在互容式觸控偵測中，當觸控發生時，第二電容Cm的電容值會變小，相對的Vm會變小，因此通過控制電路80計算Vm值的變化(即與觸控未發生時的Vm值比較)，即可得知觸控是否發生。控制電路80再根據自容式偵測電路40以及互容式觸控電路20的結果來計算出觸控發生的位置座標，及觸控程度大小。 After the charging unit 60 charges the node n to the working voltage, the mutual-capacitance detection circuit 20 can perform mutual-capacitive touch detection, and generate an output voltage Vm according to the driving signal generated by the driving unit 10. In mutual-capacitive touch detection, when a touch occurs, the capacitance of the second capacitor Cm becomes smaller and the relative Vm becomes smaller. Therefore, the change in the Vm value is calculated by the control circuit 80 (i.e. Compare the Vm value at the time of occurrence) to know whether the touch occurs. The control circuit 80 calculates the coordinates of the position where the touch occurs and the magnitude of the touch according to the results of the self-capacitive detection circuit 40 and the mutual-capacitive touch circuit 20.

值得注意的是，充電單元60可以如第4圖所示的第二實施例，獨立設置於觸控偵測電路1中。或是如第5圖所示的第三實施例，充電單元60也可以是自容偵測單元40的一部份，如此一來便不需要在電路上額外設置一個充電單元，可以節省電路空間。在第二以及第三實施例中，充電單元60可以獨立對互容偵測電路20充電，使得互容偵測電路20的運作不會受到自容偵測電路40中第一電容Cs的電壓值影響。如此一來，不論自容式觸控偵測的結果為何，即使是觸控發生而導致Vs於ts階段內所達到的電壓過低，互容式觸控偵測都可順利運作。在本發明中，充電單元60可以是電壓源或電流源。 It is worth noting that the charging unit 60 may be independently provided in the touch detection circuit 1 as in the second embodiment shown in FIG. 4. Or the third embodiment shown in FIG. 5, the charging unit 60 may also be a part of the self-capacity detecting unit 40, so there is no need to provide an additional charging unit on the circuit, which can save circuit space. . In the second and third embodiments, the charging unit 60 can independently charge the mutual capacitance detection circuit 20 so that the operation of the mutual capacitance detection circuit 20 is not affected by the voltage value of the first capacitor Cs in the self-capacitance detection circuit 40. influences. In this way, regardless of the result of the self-capacitive touch detection, the mutual-capacitive touch detection can operate smoothly even if the touch occurs and the voltage reached by VS in the ts phase is too low. In the present invention, the charging unit 60 may be a voltage source or a current source.

請參考第6圖，第6圖為本發明第四實施例。第四實施例中的觸控偵測電路1包含一驅動單元10、一互容偵測電路20、一自容偵測電路40、一控制電路80、一充電單元60以及一轉換單元82。轉換單元82用來將互容偵測電路20以及自容偵測電路40的訊號轉換成數位訊號，並將此數位訊號傳送到控制電路80，以便控制電路80計算出偵測結果。 Please refer to FIG. 6, which is a fourth embodiment of the present invention. The touch detection circuit 1 in the fourth embodiment includes a driving unit 10, a mutual capacitance detection circuit 20, a self-capacitance detection circuit 40, a control circuit 80, a charging unit 60, and a conversion unit 82. The conversion unit 82 is used to convert the signals of the mutual capacitance detection circuit 20 and the self-capacitance detection circuit 40 into digital signals, and transmit the digital signals to the control circuit 80 so that the control circuit 80 calculates the detection result.

通過本發明的觸控偵測電路及方法，在進行互容式觸控偵測的同時也可以進行自容式觸控偵測，藉此提高多點觸控的準確度，減少環 境對觸控偵測結果造成的影響，或避免面板上的水珠、汙漬或灰塵造成觸控的誤判，並且通過本發明的觸控偵測電路及方法，可以有效地縮短觸控偵測所需的時間，提高觸控感測的運行效率。 With the touch detection circuit and method of the present invention, self-capacitive touch detection can be performed at the same time as mutual-capacitive touch detection, thereby improving the accuracy of multi-touch and reducing The effect of the environment on the touch detection result, or to avoid misjudgment of touch caused by water drops, stains or dust on the panel, and the touch detection circuit and method of the present invention can effectively shorten the touch detection The time required to improve the operating efficiency of touch sensing.

雖然本發明已以較佳實施例揭露，然其並非用以限制本發明，任何熟習此項技藝之人士，在不脫離本發明之精神和範圍內，當可作各種更動與修飾，因此本發明之保護範圍當視後附之申請專利範圍所界定者為準。 Although the present invention has been disclosed in a preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. The scope of protection shall be determined by the scope of the attached patent application.

Claims (9)

一種觸控偵測電路，其包含：一驅動單元，用來產生一驅動訊號；一自容偵測電路，用來產生一自容偵測結果；一互容偵測電路，當該自容偵測電路以及該互容偵測電路之間節點的電壓達到一參考電壓時，接收該驅動訊號進行互容偵測，產生一互容偵測結果；一控制電路，接收並計算該自容偵測結果以及該互容偵測結果，以產生一偵測結果。A touch detection circuit includes: a driving unit for generating a driving signal; a self-capacitance detection circuit for generating a self-capacitance detection result; a mutual capacitance detection circuit for the self-capacitance detection When the voltage of the node between the test circuit and the mutual capacitance detection circuit reaches a reference voltage, the driving signal is received for mutual capacitance detection to generate a mutual capacitance detection result; a control circuit receives and calculates the self-capacitance detection Result and the mutual capacitance detection result to generate a detection result. 如申請專利範圍第1項所述之觸控偵測電路，其另包含一轉換單元，用來將該自容偵測電路或該互容偵測電路的訊號轉換成一數位訊號。The touch detection circuit according to item 1 of the patent application scope further includes a conversion unit for converting the signal of the self-capacitance detection circuit or the mutual-capacitance detection circuit into a digital signal. 如申請專利範圍第1項所述之觸控偵測電路，其另包含一充電單元，用來使該自容偵測電路以及該互容偵測電路之間的電壓達到一參考電壓。The touch detection circuit according to item 1 of the patent application scope further includes a charging unit for enabling the voltage between the self-capacitance detection circuit and the mutual-capacitance detection circuit to reach a reference voltage. 如申請專利範圍第1項所述之觸控偵測電路，其中該自容偵測電路偵測一第一電容，當一預定時間內，該第一電容的電壓小於一預設值時，或是該第一電容的電壓與該參考電壓的差大於一預設值時，該自容偵測結果為觸控發生。The touch detection circuit according to item 1 of the scope of patent application, wherein the self-capacitance detection circuit detects a first capacitor, and when the voltage of the first capacitor is less than a preset value within a predetermined time, or When the difference between the voltage of the first capacitor and the reference voltage is greater than a preset value, the self-capacitance detection result is that touch occurs. 如申請專利範圍第1項所述之觸控偵測電路，其中該自容偵測電路偵測一第一電容，當該第一電容充電到該參考電壓所需的時間大於一預設值時，該自容偵測結果為觸控發生。The touch detection circuit according to item 1 of the scope of patent application, wherein the self-capacitance detection circuit detects a first capacitor, and when the time required for the first capacitor to charge to the reference voltage is greater than a preset value , The self-capacitance detection result is that touch occurs. 一種觸控偵測方法，其包含：對一互容偵測電路以及一自容偵測電路之間的節點充電，在充電過程進行自容偵測；偵測該自容偵測電路偵測一第一電容，以得到該第一電容在一預設時段內的一電壓變化；在該節點的電壓達到一參考電壓時，該互容偵測電路偵測一第二電容，以得到該第二電容之一電壓輸出訊號；一控制電路根據該電壓輸出訊號計算電壓變化，以得到一偵測結果。A touch detection method includes: charging a node between a mutual capacitance detection circuit and a self-capacitance detection circuit, and performing self-capacitance detection during the charging process; detecting the self-capacitance detection circuit detects a The first capacitor to obtain a voltage change of the first capacitor within a preset period; when the voltage of the node reaches a reference voltage, the mutual capacitance detection circuit detects a second capacitor to obtain the second capacitor A voltage output signal from one of the capacitors; a control circuit calculates a voltage change according to the voltage output signal to obtain a detection result. 如申請專利範圍第6項所述之觸控偵測方法，其另包含一轉換單元，用來將該電壓變化以及該電壓輸出值轉換成數位訊號。The touch detection method described in item 6 of the patent application scope further includes a conversion unit for converting the voltage change and the voltage output value into a digital signal. 一種觸控偵測方法，其包含：對一互容偵測電路以及一自容偵測電路之間的節點充電，在充電過程進行自容偵測；該自容偵測電路偵測一第一電容，以得到該第一電容達到一參考電壓所需的一時間值；當該節點的電壓達到一參考電壓時，該互容偵測電路偵測一第二電容，以得到該第二電容之一電壓輸出訊號；根據該電壓輸出訊號計算電壓變化，以得到一偵測結果。A touch detection method includes: charging a node between a mutual capacitance detection circuit and a self-capacitance detection circuit, and performing self-capacitance detection during the charging process; the self-capacitance detection circuit detects a first Capacitor to obtain a time value required for the first capacitor to reach a reference voltage; when the voltage of the node reaches a reference voltage, the mutual capacitance detection circuit detects a second capacitor to obtain the second capacitor A voltage output signal; a voltage change is calculated according to the voltage output signal to obtain a detection result. 如申請專利範圍第8項所述之觸控偵測方法，其另包含將該電壓輸出訊號轉換成數位訊號。The touch detection method according to item 8 of the patent application scope, further comprising converting the voltage output signal into a digital signal.
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